Electropneumatic brake



Dec; 2o, 1927."

T. H. THOMAS` ELECTROPNEUMATIC BRAKE Filed Jan. 4. 1927 INVENTOR THOMAS H THOMA ATTORNEY Patented Dec. 20, 1927.

PATENT ePricerHOMAS H. THOMAS, OF EDGEWOOD, PENNSYLVANIA, ASSIG-NOR 'IOiv'IIK-IIEk WESTING- HOUSE AIR BRAKE COMPANY, OF

0F PENNSYLVANIA.

WILMERDING, PENNSYLVANIA, A CORPORATION ELECTROLPNEUMATIC BRAKE.

Application filed January 4, 192,7. Serial No, 15,8,984s` This invention relates to electro-pneu@ matic ybrakes and liasfor its kprincipal object to provide an electro-pneumatic brake system in which the application andrelease of the brakes are controlled through a single train wire. i n

In the accompanying drawing; Fig. 1 is a diagrammatic view o i an electro-pneu matic brake system embodying my, inven- 10` tion, as applied to an electrically propelled vehicle and three cars; and Fig. 2` a view,

vpartly in section, of the brake equipment employed on each car. y

As shown in Fig. 1 of the drawing, each car is provided with ay release magnet valve device 1, an application magnet valve de-r vice 2, two rectiers or devices adapted toy permitthe flow of current only in .one direction, 3 and 4l, a brake cylinder 5, an auxiliary reservoir 38, a iiuid pressure supply pipe 6 connected to the reservoir 38 through a check valve 391 andl an electric train wire 7. On the locomotive is provided a generator 8 having its leads connected to a double throw switch device 9. I

The release magnet valve device 1 comprises a magnet 10 and a casing having a chamber 11 containing a double beat valve i 12 adapted to be operated by saidmagnet,

and a chamber 13 containing a coil spring 111 adapted to engage a collared stem 15 ses cured to the valve 12.

The application magnet valve device 2 comprises a magnet 16 and a casing having a chamber 17 containing a valve 18, adapted to be operated by said magnet, and a chamber 19 containing a coil spring 20 adapted to engage a collared stemk 21 secured to the valve 18. i

The fluid pressure supply pipe 6 and-the train wire 7 on each car are adapted to be connectedfbetween adjoining cars, `so as to form a continuous pipe line and` electric train wire, throughout the train,

The rectiiiers 3 and 4 are disposed in shunt circuits around the magnets 16 andlQ respectively, and are adapted to permit thek flow or electric current only in one direction, as indicated byA the arrow on each rectifier. lThe resistance oi each shunt cirvof current that flows .through the magnet insuiiicient to operate said mag-net. For eX- ample, thecurrent flowingk from wire 7 to wire 23, Hows through the rectifier 3 and is; prevented from `iiowing. through the shunt circuit around magnet` 10 by the rectifier 4. Said current therefore `Hows through wire 26'` andinagnet 10. The small amount of cur-` rent that flows through themagnet 16, in thisV instance, ris in suiiicientto operate said magnet. 1n the same manner, when current is flowingin the reverse direction, the magnet 16 is energized While the, magnet 10 remains substantially deenergized.

Inoperation, assuming the luidpressu-re supplyr pipe charged withluid under pres sure, fluid under pressureis supplied from sald pipe on eac-h car through the checky valve 39 tothe auxiliary reservoir 38, charg-` ing said reservoir.

With, the double throw switch 9 in the position a-a, as shown inFig. 1, the elec-` tric current supplied by the generator S, f flows from the positive pole 22 of said generator. to the train wire 7, thence throughthe branch wires 23 and 241, therectifier 3 and wires 25, and 26 to the magnet 10, energizing said magnet, and thence through the wire 27 to the ground 28, through which the circuit is completed to the ground 29at theloco motive, and thence to the negativepole 30` v CUD Vbrake cylinder pressure equals that in passage 31. The brake cylinder 5 being connected to chamber 19 through pipe 33, and passage 31 being vented to the atmosphere, when the magnet 16 is energized, the brake cylinder is connected to the atmosphere, thus providing for the release of the train brakes.

To effect an application of the brakes, the double throw switch 9 is moved to position ZJ-Z as shown in dotted lines, in`

which position the circuit from the generator 8 is broken, thereby deenergizing the magnet 10, so that the pressure of spring 11iis permitted to shift the double eat valve 12 to its upper seat and thus close communication from chamber 11 to the atmospheric passage 32.

YVith the valve lseated in its upper position, fluid under pressure from the auX- iliary reservoir 38 iiows through pipe Z10 in'- to spring chamber 13, thence to valve chamber 11 and through passage 31 .to valve chamber 17, and since the application magnet 16 is also deenergized so that the valve 18 is in open position, fluid from the aurilial)T reservoir flows from chamber 1l' into spring chamber 19 and through pipe 33 to the brake cylinder 5, thus causing an application of the brakes. So long as magnet 16 `remains deeuergized, fluid from the auxiliary reservoir will continue to iiew to the brakecylinder7 as described above, until the the auxiliary reservoir.

It, however, it is desired to limit the brake cylinder pressure to some degree less than the equalization pressure, or to graduate the application of the brakes, when the desired pressure is attained in the brake cylinder, the operator moves the double throw switch from application position bto lap position 0 0, shown in dotted lines, in which the positive pole 22 yoi the generator 8 is connected to the ground 29, and the negative pole 30 is connected to the train wire 7 by way ot wire 341. The generator current then flows from the positive pole 22 et the generator, through the ground 29 to the ground 28 on the car, thence through wires 27 and 35, rectifier 4, wires f and 26, magnet 16 and through `wires 37 and 23 to the train wire 7 and through wire 811 to the negative pole 30 et the generator. The magnet 16, being thus energized, operates to close the valve 18 so as to prevent further flow from the auxiliary reservoir to the brake cylinder 5.

When the valve 18 is closed by energization of the magnet 16, the double beat valve 1Qv is seated in its upper position, since the magnet 10 is deenergiaed. However, the position of the double beat valve 12 is immaterial at this particular time.

By alternately moving the double throw switch 9 to the posit-ions .7J-b and 0 0, re-

spectively, so as to alternately energize and deenergize the magnet 16, the brake cylinder pressure may be increased in steps up to the degree at which the auxiliary reservoir equalizes into the brake cylinder.

To release the brakes, the double throw switch 9 is moved to the release position ca -e, in which the magnet 10 is energized, and shifts the double beat valve 12 to its lower seat, and the magnet 16 is deenergized so that the valve 18 is unseated. Thus the brake cylinder oisl connected to the atmosphere and release of iluid in the brake cylinder is ellected;

It it is desired to graduate the release of the brakes, the double throw switch 9is moved Ytrom release position ama to lap position c-c, in which themagnet 16 is energized, and operates to seat the valve 18 so as to prevent further flow of lluid from the brake cylinder to the atmosphere. By alternately moving the double throw switch 9 from position e-e to position c-c, the brake cylinder pressure may be reducedl in steps, as desired.

1n graduating` the release oi" the brakes the double beat valve 12 is seated in .its upper position by the deeneroization ol magnet 1,() when the valve 18 is seated, but this movement of the double beat valve 12 has no effect upon the brake operation at sit-ion b-b, in which ne current is supplied lllll through the train wire, consequently, `both the application magnet 16 and the release magnet 10 are deenergized. This is very desirable, since in. case the train wire 7 be comes broken,` or if the current should i'ail from any cause, an application ot the brakes will be automatically eliiected and the train brought to a stop. 'he brakes cannot their be released and the train started until the circuit has been repaired or the current supply restored. f

The check valve 39 is placed in the pipe connecting the fluid pressure supply pipe 6 to the auxiliary reservoir 3S, so tl'iat in case ot' the rupture et said pipe, as would occur in case ot a train breaking in two, a supply oi? tluid under pressure is retained on `each car to apply the brakes. Y Having now described my invention, what I claim as new and desire to secure by Letters Patent, is

1. The combination with two electrically controlled devices for controlling the application and release of the brakes and a single train wire through which current is supplied to both devices, o'l' means for preventing the effective energization oi' one device when the other deviceis energized by flow of current through said wire.

2. The combination with two electrically lll) .neuen-3o controlled devices yfor i controlling a the 'applicationV and sreleasefof thefbrakes and :a single to f both, devicespof means Yfor :preventing the e operative energization of one deviceewhen the other device is energized by flow of current through said wire.;

3. The combination With tivo electrically controlled devices for controlling the application and release of the brakes and a single train wire through which current is supplied to both devices, Vof means for preventing the effective energization of one device by current flowing' through said Wire in one direction While the other device is effectively energized by said floW of current.

4. The combination with an electrically controlled device for controlling the brakes and having a shunt circuit through Which' current flows in one direction, of means in said circuit for preventing the flow of current through said circuit in `the opposite direction.

5. The combination With tvvo electrically controlled devices arranged in series and supplied with current from a single train Wire and each device having a shunt circuit, of means in one shunt circuit for preventing the flow of current in one direction `and means in the other shunt circuit for preventing the flow of currentin the opposite direc# tion.

6. In an electro-pneumatic brake, the combination withv a brake cylinder, of electrically controlled valve means for controlling the supply and release of fluid under pressure to and from the brake cylinder and electri-v cally controlled valve means for controlling communication through which .the first mentioned valve means supplies fluid under pressure to the brake cylinder.

'7. In an electro-pneumatic brake, the combination vvith a Lbrake cylinder, of electrically controlled valvemeans for controlling the supply and release of fluid under pressure to and from the brake cylinder, electrically controlled valve means for controlling communication through Which the first mentioned valve means supplies fluid under pressure to the brake cylinder, and a single train wire through which current is supplied to operate both electrically controlled valve means. i

8. In an electro-pneumatic brake, the combination With a brake cylinder, of electrik cally controlled valve means for controlling the supply and release of fluid under presr sure to and from the brake cylinder, electrically controlled valve means for controlling communication through which the first mentioned valve means supplies fluid under pressure to the brake cylinder, a single train Wire through which current is supplied to operate both electrically controlled valve means, and means for effecting the energization of vonly one of :said Ielectrically controlled `valve means when current isrflowing through said train wire ini one direction. r

controlled kvalve ,means lfor `controlling the supply and `releasevof fluidffunder pressure to and from the brake cylinder, electrically controlled valve means for controlling communication `through which the first men-v tioned valve means supplies fluid under pressure to the brake cylinder, a single train `Wire through Which current is supplied to operate both electrically controlled valve 'means,vand means for effecting the energi- .9., Inan electrofpneumatic brake, thecomi bination Withf abrake cylinder, ofelectrically plying fluid under pressure to the brake cylinder and upon energization of said magnet for connecting said brake cylinder to the eX haust, a second electro-magnet, and a valve operated upon energization of saidmagnet for closing communication through which fluid under pressure is supplied to the brake cylinder by operation valve;

11. In an electro-pneumatic brake, the combination With a brake cylinder, of an electro-magnet, a double beat valve operated upon deenergization of said magnet for supplying fluid under pressure to the `brake cylinder and upon energization of saidk magof; said double beat net for connecting said brake cylinder to the exhaust, a second electro-magnet, a valve operated upon energization of said'second y,

magnet for closing communicationthrough which fluid under pressure is suppliedto the brake cylinder by operation of said double beat valve, and a single train Wire for controlling the current to said magnets.

12. In an electro-pneumatic brake, the combination With a brake cylinder, of an electro-magnet, a double `beat valvevoperated upon deenergization of said magnet for supplying fluid under pressure to the brake cylinder and upon energization of said magnet for connecting said brake cylinder to the exhaust, a second electro-magnet, a valve operated upon energization of said second magnet for closing communication through which fluid under pressure is supplied to the brake cylinder by operation of said double beat valve, a single train Wire connected to said magnets, and means forv energizing one magnet only When current flows through said train Wire in one direction andthe other magnet only when current flows through said train Wire in the reverse direction. y

13. A one Wire electrically controlled brake having' means for effecting the release 5 of the brakes When current is owing through said Wire in one direction, for hold-` ing the brakes applied When current is 110W- ing through said wire in the reverse direc-` tion, and for applying the brakes when no current is flowing through 'said wire. 10

In testimony whereof I havehereunto set my hand.

THOMAS H. THOMAS. 

